Foam extinguishing system



Nov.. 1,' 1932. H, HARRls 1,885,258

FOAM EXT-I NGUISHING SYSTEM Filed Aug. 9, 1928 %072 Mg IIYVENTOR.

Patented Nov. 1, 1932 UNITED STATES PATENT OFFICE GEORGE H, H R IS. OE UTICA, NEW YORK; ASSIGNOB To. AMERICAN LA FRANCE ND EQAMITEECORPORATION, or NEW YORK, Y. A CORPORATION o ew w nx FOAM nxrineursnme SYSTEM Application filed August 9, 1928. Serial No. 298,467.

The invention is a system for producing and deliver-ing foam for extinguishing fire, involving various novel features having to do with the utilization of solid materials *3 from which to make the foam and also an automatic control capable of application to a variety of; situations where it is desirable to register the exhaustion of the material being fed, all as explained below and more '10 particularly pointed out in the appended clai Fig. 1 of the accompanying drawing shows the invention, by way of diagram, but sufiiciently to enable any vperson skilled in the art to make and practice the same, and

Fig. 2 illustrates, also diagrammatically, a modification. I

In the case ofFig. l-the foam is pro duced frQm a composite powder containing acid and basic reagents, such as soda and aluminum sulphate, and a foam stabilizer,

all in a dry state and as described in Palmer Patent No. 1,591,401. Such powder is contained in a receptacle 1 of any suitable size, 2 having a discharge opening leading into the throat of an ejector or Venturi tube 2, or other suction device, which is supplied with water from a pipe 3 under suitable pressure. The suction produced by' the water in the ac throat draws the powder down into the water at a rateproportional to the water flow. The mixture of powder and water passes from the ejector through a swirler or mixer 4: and pipe 5 to a point of discharge which .35 may be over or adjacent the thing to be protected against fire. g

The receptacle 1 contains a vertical shaft (iappropriately journalled therein and arranged to be rotatedby an electric motor 7 40 This shaft carries one or more arms 8, hinged to it, QIljllOIiz'ontal axes, and of such length that they will reach close to the inner surface of the receptacle when in horizontal position. Their purpose is two-fold: first they serve, by their rotation in the powder,

to break up and stir it so that it will gravitate freely and uniformly downward into the ejector, or such other mixing device as may be employed; second, when the powder has all escaped, one of these arms,.for example the uppermost, swings out to nearly a horizontal position as the result of the de creased resistance to shaft rotation. In such extended position, the arm strikes and actuates or trips an electric switch 9 which shuts the water off as later described, so that when 1 the powder is exhausted operation of the sys-v tem stops. Thus only foam is delivered on to thething to be protected.

The mode of operation of the switch 9 will be clear from the drawing and it will be apparent that it may be constructed according to any suitable design adapted for carrying out the function stated. In the present case the two contact members of the switch are held apart against the pull of a spring by a trigger 10 and this trigger, when struck by the uppermost arm 8, releases its contact member allowing the spring to close the stopping circuit.

The system isshown as designed to be set in action automatically, as by a thermostat or fusible link, such as indicated at 11, and which will be understood to be placed in a position where it will be operated or melted by the heat of the fire. As shown, this thermostatic member, when operated, releases the weighted arm 12 of the water supply valve 13, which thenmoves under the influenceof its weight to its on position in which water flows to the ejector and in which position it is arrested and held by a magnetic latch 14. The engagement of the arm 12 with the latch 14, or the falling of the weight, closes the circuit 15 of the electric motor 7, as will be apparent in the drawing, so that the turning on of the water is inv stantly accompanied by the agitation of the powder in the supply receptacle and foam is immediately produced and delivered through t P pe The motor circuit is shown asincluding thejvalve arm 12 and the latch but this will be understood to be merely diagrammatic; the apparatus can, of course, be variously constructed so that the opening of the water supply will produce or coincide with the closure of the circuit of the motor.

The latch 14 is arranged to be withdrawn from its lever supporting position by the pull 100 of a solenoid 16 i cluded in the circuit 17 of the stopping switch 9 above referred to. When this switch is closed, as the result of exhaustion of the supply of foam-making material, the latch is withdrawn and the valve arm 12 then falls or moves to its lowest and final position, shutting ofi the water and opening the motor circuit. As a matter of economy of current, this further movement of the valve lever may also trip the trigger 18 of a switch 19 to allow the latter to open and thus shut the current off from the solenoid of the magnetic latch.

Between the water valve 13 and the throat of the ejector, the water pipe is provided with a small drain tube 20, for the purpose of venting any water leaking past the water valve and keeping it from entry into the throat where the presence of moisture might be injurious to the supply of powder in the adjacent receptacle. The flow capacity of this drain'is too small to be wasteful of water when the system is in action. A check valve 21 may also be employed as further prevention of the passage of moisture from the water pipe to the powder and preferably both the drain' and the check valve are used for this purpose.

Instead of using a single composite powder, as above described, and as employed in said Palmer patent, the present invention is adapted for use with separate powders; that is to say, one powder consisting of one reagent, for example, the aluminum sulphate, and the other, of the other re-agent and the stabilizer, for example, sodium bicarbonate and licorice extract or the like. In this case two receptacles are provided, as indicated at 22 and 23 in Fig. 2, which will be recognized as a diagram in plan. Each of these receptacles will be understood to be a substantial duplicate of the receptacle 1, shown in Fig. 1 and each provided with an agitating shaft and hinged arms thereon, as in that figure, but arranged to be driven by a single motor common to them. One of these containers is filled with one powder and the other with the other, and each receptacle delivers to an ejector 24 and 25 respectively, which ejectors are included in branch paths 26 of the water pipe 2? controlled as before by the water valve 13 and its valve arm 12. On the delivery side, the ejectors 24: and 25 discharge their respective mixtures of powder and water into the common outlet pipe 28, which corresponds to the foam pipe 5 in the case of Fig. 1. The reaction and production of foam begins at the junction with pipe 28. Otherwise the action is the same as in Fig. 1. When the powder in both receptacles is eX- hausted, the shaft speed will increase and the centrifugal arm 8 of one receptacle, for example in receptacle 2 1, strikes the trigger 10, closing the switch 9 as before, thus terminating the discharge of foam.

In both cases the shaft 6 will be understood as provided with suitable bearings in the bracket members in which it is supported and below the lowermost bracket it may carry a further stirring device, marked 29, the function of which is to break up lumps which might otherwise clog the outlet into the injector. This, as will be seen, is merely a hub with one or more inclined vanes or projections on it arranged to revolve close enough to the wall of the outlet passage to crush such lumps as may be encountered.

I claim:

1. In a foam-making system, a receptacle for solid foam-making material, a water supply, means for feeding such material to the water, a valve controlling the water supply, thermal means for causing the opening of said valve and means controlled by the'absence of said material for closing said valve.

2. In a foam. system, the combination of means for storing foam-making material, a water supply, means for continuously feed ing such material to the water, and means automatically responsive to the absence of such material in the storage means for stopping the water supply.

3. In a foam system, means for continuously mixing solid foam-making material with water, comprising storage means for such material and a water-operated ejector coacting therewith to draw the material into the water and means automatically responsive to the absence of such material in the storage means for stopping said water supply.

1. A foam system including'a receptacle containing solid foam-making material, a water supply, means for continuously feeding such material to the water and 'means responsive to the absence of such materialin the receptacle for rendering the feeding means inactive.

5. In a foam system, the combination of a receptacle containing solid foam-making material, a stirrer therein, means for conducting such material to a water stream and means for cutting off the stream operated by said stirrer.

6. In a system for feeding dry'material to a water stream, a receptacle containing asup? ply of the material, a movable member Within the receptacle normally restrained from operative movement by the resistance opposed by the presence of said material in the receptacle, and a control member adapted to be engaged by said member when it overcomes said resistance.

7. In a system for feeding dry material, a receptacle for such material, a moving device therein normally submerged in said material and having a greater or a different movement when said material is absent, and'a control member adapted to be engaged by said device.

8. In a system for feeding dry material, a receptacle for such material, a stirrer therein comprising one or more arms subject to movement by centrifugal action, and means adjacent the wall of said receptacle adapted to be engaged and rendered operative by one of said arms.

9. In a foam system, a water supply, a Water passage therefor having a valve, a receptacle for dry foam-making material in communication with said passage, an outlet for foam at the end of said passage and a drain provided in said passage at a point between said valve and the communication with said receptacle adapted to prevent accidental passage of moisture to said receptacle.

10. In a foam-making system, a storage receptacle for dry foam-making material, a'

Water-operated ejector connected with the outlet of said receptacle, a shut-off valve, a check valve between said valve and the receptacle and a drain between the check valve and said shut-ofi valve. I

11. In a fire extinguishing system the combination with means for storing fire extinguishing material, a water pipe and control valve therefor, means for mixing said mate rial with the water when said valve is opened, means to open said valve, and means responsive to the absence of said material in the storage means for closing said water valve.

In testimony whereof, I have signed this specification.

GEORGE I-I. HARRIS. 

